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Abstract: This study is focused on forming a spider-wave-like nano-nets of nylon-6 decorated with unique mop-brush-shaped ZnO rods. The nanocomposite is prepared in two steps. First, ZnO nano-seeds containing electrospun nylon-6 nano-nets were fabricated by blending ZnO nanoparticles with nylon-6 solution. Second, the electrospun ZnO/nylon-6 composite was hydrothermalized with ZnO precursor solution to grow long ZnO mop-brush-shaped rods on the surface of fibers. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), and FT-IR revealed that simultaneous formation of spider-wave-like nano-nets and effective uploading of ZnO nano-seeds were carried out by electrospinning from the blend solution. Field-scanning electron microscopy (FE-SEM) showed that unique mop-brush-shaped ZnO rods were effectively grown on the surface of nylon-6 fibers. As-synthesized spider-wave-like nano-nets of nylon-6 decorated with large number of mop-brush-shaped ZnO rods showed good hydrophilicity, photocatalytic property, and UV-shielding property. Furthermore, uploading technique of nano-seeds with small amounts during electrospinning and successive grown of sufficient amount of mop-brush-shaped ZnO rods nucleated by these nano-seeds during hydrothermal treatment provide a good stability of ZnO rods on the surface of fibers. Therefore, as-synthesized inorganic/organic nanocomposite (IONC) fibers may be used as potential textile for water treatment and protective clothing. [Copyright &y& Elsevier]

Abstract: Polyamide-6 nanofibers containing calcium lactate (CL) on their surface were prepared by neutralization of lactic acid (LA) in core–shell structured polyamide-6/LA electrospun fibers. First, simple blending of LA with polyamide-6 solution was used for electrospinning which interestingly formed a thin LA layer around polyamide-6 nanofibers (core–shell structure) and then subsequent conversion of this LA into calcium lactate via neutralization using calcium base. FE-SEM and TEM images revealed that plasticizer capacity of LA led the formation of point-bonded structure due to the formation of shell layer of LA and core of polyamide-6. The bone formation ability of polyamide-6/calcium lactate composite fibers was evaluated by incubating in biomimetic simulated body fluid (SBF). The SBF incubation test confirmed the faster deposition of large amount of calcium phosphate around the composite polyamide-6/calcium lactate fibers compared to pristine polyamide-6. This study demonstrated a simple post electrospinning calcium compound coating technique of polymeric nanofibers for enhancing the bone biocompatibility of polyamide-6 fibers. [Copyright &y& Elsevier]

Background: A reliable assessment of mandibular invasion is crucial for treatment planning to obtain both radical tumor resection and good functional results. Purpose: To retrospectively compare the diagnostic value of three different imaging methods - computed tomography (CT), magnetic resonance (MR) imaging, 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT - and their combined use for detection of mandibular invasion by squamous cell carcinoma (SCC) of the oral cavity. Material and Methods: Forty-six patients (39 men and 7 women; mean age, 59.4 years) suspected of having mandibular invasion by SCC of the oral cavity underwent CT, MR, and PET/CT within 2 weeks before surgery. First, each study was reviewed separately for the presence of mandibular invasion by tumors. Then, the value of combined images was assessed based on a confidence rating score for each modality assigned by observers. These results were verified with histopathologic findings. Results: Histopathologic examination revealed mandibular invasion in 12 of 46 SCCs. The sensitivity, specificity, and accuracy were 41.7%, 100%, and 84.8% for CT; 58.3%, 97.1%, and 87.0% for MR; and 58.3%, 97.1%, and 87.0% for PET/CT, respectively. The comparison of these modalities showed no statistically significant difference among them ( P > 0.05). The combination of CT, MR, and PET/CT improved sensitivity (83.3%), without loss of specificity (100%) and accuracy (95.7%), although the difference failed to reach statistical significance ( P > 0.05). Conclusion: The combined analysis of CT, MR, and PET/CT can improve sensitivity in the detection of mandibular invasion by SCC of the oral cavity. [ABSTRACT FROM AUTHOR]

Abstract: Flow stress during hot deformation depends mainly on the strain, strain rate and temperature, and shows a complex and nonlinear relationship with them. A number of semi-empirical models were reported by others to predict the flow stress during hot deformation. This work attempts to develop a back-propagation neural network model to predict the flow stress of Ti–6Al–4V alloy for any given processing conditions. The network was successfully trained across different phase regimes (α+β to β phase) and various deformation domains. This model can predict the mean flow stress within an average error of ∼5.6% from the experimental values, using strain, strain rate and temperature as inputs. This model seems to have an edge over existing constitutive model, like hyperbolic sine equation, and has a great potential to be employed in industries. [Copyright &y& Elsevier]

Abstract: Ti–6Al–4V ELI (extra low interstitials) grade alloy provides improved ductility and fracture toughness comparing to grade 5 Ti–6Al–4V alloy. In order to find the optimum superplastic forming and diffusion bonding (SPF/DB) condition, a series of tensile tests was carried out at the strain rate range of 10−4 to 10−2 s−1 and temperature range of 1073–1223K. The maximum elongation of 1898% was obtained at the strain rate of 10−3 s−1 at 850°C. It was shown that the ELI grade alloy performs better than the grade 5 alloy in terms of the optimum superplastic condition for Ti–6Al–4V. Based on this result, diffusion bonding process of superplastic Ti–6Al–4V ELI sheet metals was developed. Bonding was completed by means of inert gas pressure applied in a bonding tool at high temperature. The microstructure of the bonding area was investigated and the bonding interface was microscopically undetectable. The evidence of nucleation of new grains and migration of grain boundaries at the interface proves the diffusion bonding process is successful. It is shown that the superplastic forming and diffusion bonding of Ti–6Al–4V ELI grade is possible at the temperature lower than those of conventional Ti–6Al–4V. [Copyright &y& Elsevier]

Epstein–Barr virus (EBV) is a B-lymphotropic human herpes virus that infects B lymphocytes and is associated with a broad spectrum of benign and malignant diseases. B cell infection by EBV causes indefinite cell proliferation that results in the development of immortalized lymphoblastoid cell lines (LCLs). We found that SNU-1103, a latency type III EBV-transformed LCL developed from a Korean cancer patient, resisted the G1 arrest that was normally caused by serum starvation. Western blot analyses revealed several alterations in the expression of key regulatory cell cycle proteins involved in the G1 phase. High expression of cyclin D2 and time-dependent increases in cyclin-dependent kinase 6 (CDK6) and cyclin D3 were observed in SNU-1103 during serum starvation. Very unexpectedly, in SNU-1103, the key G1 phase CDK inhibitor p21[sup Cip1] was expressed at a consistently high level, while p27[sup Kip1] expression was increased. Of three pRb family proteins, pRb expression was reduced and it became hypophosphorylated in SNU-1103 during serum starvation. Instead, p107 and p130 were expressed at consistently high levels in SNU-1103 during serum starvation. In conclusion, compared with an EBV-negative BJAB cell line, multiple cell cycle regulatory proteins were abnormally or inversely expressed in SNU-1103 during serum starvation.Key words: Epstein–Barr virus, lymphoblastoid cell line, B lymphocyte, serum starvation, cell cycle proteins.Le virus Epstein–Barr (EBV) est un herpèsvirus B-lymphotrope humain qui infecte les lymphocytes B et est associé a de nombreuses maladies bénignes ou malignes. L'infection des lymphocytes B par EBV engendre une prolifération cellulaire illimitée, ce qui entraîne le développement de lignées cellulaires lymphoblastiques (LCL) immortalisées. Nous avons noté que les cellules SNU-1103, une LCL obtenue à partir de cellules tumorales d'un Coréen transformées par le EBV latent de type III, ne s'arrêtent pas en phase G1 comme le font normalement les cellules cultivées en absence de sérum. Des transferts de type Western montrent plusieurs modifications de l'expression d'importantes protéines de régulation du cycle cellulaire qui interviennent au cours de la phase G1. Une forte expression de la cycline D2 et une augmentation de la CDK6 et de la cycline D3 en fonction du temps sont notées dans les cellules SNU-1103 cultivées en absence de sérum. Il est très surprenant de constater que l'inhibiteur p21[sup Cip1] de la CDK, essentiel au cours de la phase G1, est constamment exprimé à taux élevé dans les cellules SNU-1103 et que l'expression de p27[sup Kip1] est augmentée. Pour ce qui est de trois protéines de la famille de pRb, l'expression de pRb est réduite et pRb devient hypophosphorylée dans les cellules SNU-1103 cultivées en absence de sérum. Par contre, les protéines p107 et p130 sont toujours exprimées à taux élevé dans les cellules SNU-1103 cultivées en absence de sérum. En conclusion, comparativement à la lignée de cellules BJAB non infectée par EBV, de nombreuses protéines de régulation du cycle cellulaire sont exprimées de façon anormale ou inverse dans les cellules SNU-1103 cultivées en absence de sérum.Mots clés : virus Epstein–Barr, lignée cellulaire lymphoblastique, lymphocyte B, absence de sérum, protéines du cycle cellulaire.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

Direct energy deposition (DED) is a highly applicable additive manufacturing (AM) method and, therefore, widely employed in industrial repair-based applications to fabricate defect-free and high degree precision components. To obtain high-quality products by using DED, it is necessary to understand the influence of the process parameters on the product quality. The optimization of such processing parameters provides several advantages such as minimization of the loss of material and time. However, the optimization of the complex relationship between the process parameters-geometry-properties of the fabricated sample is difficult to realize and requires significant experimentation. Herein, a computational model based on artificial neural networks was developed to optimize process parameters for DED-processed Ti-6Al-4V alloy. The model was developed to estimate the density and build height (the actual build height realized after fabrication) of the sample as a function of power, scan speed, powder feed rate, and layer thickness. The optimum model with high-accuracy predictions was employed to construct the process maps for the DED-processed Ti-6Al-4V. The relative importance indices of process parameters on the build height and density were investigated. Further, the effect of power and scan speed on the microstructure of Ti-6Al-4V alloy was discussed. Finally, based on the obtained results, the optimum fabrication conditions for the DED-processed Ti-6Al-4V alloy were determined. [ABSTRACT FROM AUTHOR]

We present an integrated design and fabrication strategy for the development of hierarchically structured biomechanically and biologically functional tissue scaffold. An integration of β-TCP incorporated fluffy type nanofibers and biodegradable interpenetrating gelatin-hydrogel networks (IGN) result in biomimetic tissue engineered constructs with fully tunable properties that can match specific tissue requirements. FESEM images showed that nanofibers were efficiently assembled into an orientation of IGN without disturbing its pore architecture. The pore architecture, compressive stiffness and modulus, swelling, and the biological properties of the composite constructs can be tailored by adjusting the composition of nanofiber content with respect to IGN. Experimental results of cell proliferation assay and confocal microscopy imaging showed that the as-fabricated composite constructs exhibit excellent ability for MC3T3-E1 cell proliferation, infiltration and growth. Furthermore, β-TCP incorporated functionalized nanofiber enhanced the biomimetic mineralization, cell infiltration and cell proliferation. Within two weeks of cell-seeding, the composite construct exhibited enhanced osteogenic performance (Runx2, osterix and ALP gene expression) compared to pristine IGN hydrogel scaffold. Our integrated design and fabrication approach enables the assembly of nanofiber within IGN architecture, laying the foundation for biomimetic scaffold. • Biomimetic scaffold with channel-like macroporous architecture is developed. • First time bioactive fluffy type nanofibous mesh is integrated with GelMA hydrogel. • Nanofibers were efficiently assembled an orientation of hydrogel network. • Fibers do not interrupt the macroporous architecture of GelMA. • The pore architecture, stiffness, modulus, and the bioactivity can tailored. [ABSTRACT FROM AUTHOR]

Owing to the high production cost of a high alloying system, the commercialization of β-Ti alloys with high elastic admissible strain (= yield strength/elastic modulus) for biomaterials is challenging. To reduce the alloying elements and maintain a high elastic admissible strain, a new alloy design of the metastable α+β-Ti alloy (Ti–4Al–2Mo–2Fe–2Cr) is proposed in this study. The microstructure of the alloy consists of an α phase with a high yield strength and a metastable β phase with a low elastic modulus. The existence of the hard α phase increases the critical stress for stress-induced martensitic transformation due to stress and strain partitioning. In addition, heat treatment in the α+β regime is an effective method for grain refinement, resulting in high strength without increasing the elastic modulus. This alloy exhibited an excellent combination of strength and ductility with a high elastic admissible strain. Moreover, electron backscattering diffraction and field-emission transmission electron microscopy were used to understand the mechanical behavior of the α+β Ti alloy. [ABSTRACT FROM AUTHOR]

Phenolics from plant materials have garnered attention in nanomedicine research, due to their various medicinal properties. Caffeic acid, a phenolic compound that is abundant in coffee beans, has been proven to have anticancer effects, due to its reactive oxygen species (ROS)-inducing properties. Here, a supramolecular nanomedicine was designed using caffeic acid molecule and the synthetic anticancer drug bortezomib, via catechol–boronic acid conjugation and Fe(III) ion crosslinking. Bortezomib is a proteasome-inhibiting drug and its boronic acid functional group can bind to caffeic acid's catechol moiety. By having a nanoparticle formulation that can deliver bortezomib via intracellular endocytosis, the catechol–boronic acid conjugation can be dissociated, which liberates the boronic acid functional group to bind to the 26S proteasome of the cell. The ROS-inducing property of caffeic acid also complements the bortezomib payload, as the latter suppresses the survival mechanism of the cell through NF-κB inhibition. [ABSTRACT FROM AUTHOR]

Ultrafine-grained (UFG) structure is beneficial for overcoming the strength-ductility trade-off and enhancing the superplasticity of two-phase Ti alloys. Recently, it has been demonstrated that compression with decreasing temperatures is effective for producing UFG two-phase Ti alloys initially with lamellar microstructures. However, the effect of lamellar thickness on the microstructural evolution during this process has not yet been fully elucidated. In this study, Ti-6Al-4V alloys with different lamellar thicknesses were compressed while the processing temperature was decreased from 800°C to 600°C. The thinner lamellar microstructure was preferable for preventing void/crack formation, while accelerating the continuous dynamic recrystallisation, thus providing a fully UFG structure at a relatively low strain of 1.4. In addition, the origin of different plastic flows in each sample was analysed in detail by analysing the microstructural evolution. These findings demonstrate that the processing method is effective for reducing the grain size of a two-phase Ti alloy without severe plastic deformation techniques, which require large strain (≥4). A reduction in the strain required to achieve the UFG structure would be beneficial because conventional metal-forming processes, i.e. rolling, extrusion, or forging, which are suitable for mass production, could be used. [ABSTRACT FROM AUTHOR]

A pH-sensitive polymeric carrier was developed in this study for local delivery of anticancer drug bortezomib (BTZ) to cancer cells. Our strategy is based on the conjugation of BTZ to polymeric carriers containing catechol groups, which are considered to release BTZ selectively in cancer cells. In this study we used alginate-conjugated polydopamine as a building block polymer. The catechol moiety of polydopamine binds to the boronic acid group of BTZ drug and release the drug molecules in a pH-dependent method. Cancer tissue has acidic environment where BTZ dissociate from the catechol group of polydopamine to control the release of the free drug. Mathematical equation models were used to clarify the mechanism of drug release. The release profile fitted first order with correlation coefficient (R2 = 0.98), the release mechanism was studied using Korsmeyer–Peppas, Higuchi, Hixson-Crowell, and Kopcha models. We revealed the release mechanism follows non-fickian and diffusion was the dominant mechanism while small portion contributed to erosion. The pH-sensitive mechanism controls the release of BTZ in targeted cancer cells, hence developing a novel idea that is applicable in future towards other boronic acid-containing drugs to treat various kinds of health challenges. • The AlgPD-BTZ hydrogel presented a chemo selective approach for cancer chemotherapy. • Sustained release profile of BTZ in pH dependent manner • In-depth study of kinetics and mechanism of drug release • The AlgPD-BTZ hydrogel shows remarkable cytotoxicity to cancer cells. [ABSTRACT FROM AUTHOR]

We used selective laser melting (SLM) to produce a three-dimensional specimen of pure Ti and found that an equiaxed grain structure and weak crystallographic texture could be achieved simultaneously via subsequent heat treatment. These traits have never been attained simultaneously in pure Ti prepared by traditional methods such as casting and rolling. This remarkable achievement was possible because recrystallization occurred during heat treatment without plastic deformation; such deformation introduces stored energy that drives recrystallization but inevitably causes a strong texture to develop. The occurrence of recrystallization was attributed to unique features of the SLM process including a very high cooling rate and repetitive layer stacking. These features generated considerable stored energy by affecting solidification and the β → α phase transformation. Steep in-grain orientation gradients and a fine lath structure also contributed to the activation of recrystallization by facilitating recrystallization nucleation. The heat-treated specimen showed tensile properties with significantly reduced anisotropy. This finding will provide new strategies for developing isotropic metallic materials and may introduce new applications of SLM. • A three-dimensional specimen of pure Ti was produced using selective laser melting. • Both equiaxed structure and weak texture were achieved by subsequent heat treatment. • These traits cannot be attained simultaneously by traditional manufacturing methods. • This desirable ability of SLM originates from unique features of SLM process. • The heat-treated sample had significantly reduced anisotropy in tensile properties. [ABSTRACT FROM AUTHOR]

• Unique three-dimensional graphene/mixed transition metal oxides modified activated carbon was prepared and characterized. • The nanocomposite electrode shows low charge transfer resistance and high specific capacitance. • Analysis of synchrotron-based hard X-ray absorption spectroscopy. • The fabricated nanocomposite exhibits a high electrosorption capacity of 9.34 mg g−1. Over the last two decades, the capacitive deionization (CDI) technique has been developed into a high performance, low-cost, and environmental-friendly desalination technology. The development of novel advanced nanostructures via the hybridization of diverse carbon materials to improve the performance of CDI technology has attracted considerable attention. In this study, the combination of graphene hydrogel and ZrO 2 -doped TiO 2 nanofibers as efficient dopants into activated carbon (AC), has been achieved through a simple electrospinning technique followed by a post annealing process. The strong interactions between the graphene hydrogel, nanofibers and AC were found to enhance the wettability as well as the electrical conductivity of the AC. The morphology and electrochemical performance of the as-synthesized composite were characterized by field-emission scanning electron microscopy (FE-SEM), Transmission electron microscopy (TEM), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). What's more, the X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and synchrotron X-ray absorption structures (XAS) are performed to investigate the atomic and electronic structure of titania and zirconia in order to understand their phase stability. We observed the appearance of anatase structure of titania and cubic structure of zirconia after doping the AC and graphene hydrogel with the nanofibers. The water contact angle of the composite was examined and found to be less than 3°. The introduced nanocomposite showed high electrosorption capacity of 9.34 mg g−1 at the initial solution conductivity of ∼100 μS cm−1, which is much higher compared to the other surveyed materials; these results should be attributed to its significant hydrophilicity, high specific capacitance, and reduced charge transfer resistance. [ABSTRACT FROM AUTHOR]

A fibrous scaffold, fully assimilating polyurethane (PU) and silk fibroin associated with functionalized multi-walled carbon nanotubes (f MWCNTs) was developed by electrospinning technique. Herein, we engineered the PU/Silk fibroin- f MWCNTs-based biomaterial that shows great promise as electrospun scaffolds for neuronal growth and differentiation, because of its unique mechanical properties, hydrophilicity, and biodegradability, with outstanding biocompatibility in nerve tissue engineering. The morphology and structural properties of the scaffolds were studied using various techniques. In particular, the presence of f MWCNTs enhances the electrical conductivity and plausible absorption of sufficient extracellular matrix (ECM). The in vitro tests revealed that the aligned scaffolds (PU/Silk- f MWCNTs) significantly stimulated the growth and proliferation of Schwann cells (S42), together with the differentiation and spontaneous neurite outgrowth of rat pheochromocytoma (PC12) cells that were particularly guided along the axis of fiber alignment. The conductive PU/Silk- f MWCNTs scaffold significantly improves neural expression in vitro with successful axonal regrowth, which was confirmed by immunocytochemistry and qRT-PCR analysis. Inspired by the comprehensive experimental results, the f MWCNTs-based scaffold affords new insight into nerve-guided conduit design from both conductive and protein rich standpoints, and opens a new perspective on peripheral nerve restoration in preclinical applications. • Polyurethane-silk/multiwall carbon nanotubes based aligned electrospun scaffold was fabricated. • A protein rich biomaterial showed high mechanical strength and good electrical conductivity. • PC12 cells are well proliferated and differentiated on scaffold along with fibers orientation. • The scaffold exhibited strong bioactivity, suited for in vitro nerve cell regeneration. [ABSTRACT FROM AUTHOR]

• Tensile properties of 18Cr-12Ni-Mo steels were modeled using neural networks. • Graphical user interface (GUI) was developed for easy use. • The model was able to correlate the relationships between input-output variables. • A virtual 18Cr-12Ni-Mo steels were created with mean values of the databases. • Effect of temperature and composition on properties was estimated accurately. An artificial neural network (ANN) model was designed to correlate the complex relations among composition, temperature, and mechanical properties of 18Cr-12Ni-Mo austenitic stainless steels. The developed model was used to estimate the composition-property and temperature-property correlations with 97% and 91% accuracy, for train and unseen test datasets. The ANN predictions are more accurate with experimental results as compared with the calculated properties of the existing model. The effective response of the alloying elements on the mechanical properties at ambient as well as elevated temperatures was quantitatively estimated with the help of the index of relative importance (I RI). The calculated results of the ANN model beneficial for both researchers as well as designers to guide actual experiments. Hence, this proposed technique will be helpful in developing the components of austenitic stainless steel with desired properties. [ABSTRACT FROM AUTHOR]

Asymmetrically porous and aligned fibrous tubular conduit with selective permeability as a biomimetic neural scaffold was manufactured using polycaprolactone (PCL), silk, and quercetin by a modified electrospinning method. The outer surface of the randomly oriented fibrous scaffold had microscale pores that could prevent fibrous tissue invasion (FTI), but could permeate neurotrophic factors, nutrients, and oxygen. The inner surface of the aligned fibrous scaffold can be favorable for neurite outgrowth, because of their superior neural cell attachment, migration, and directional growth. In vitro and in vivo studies have demonstrated the therapeutic effect of Quercetin, a ubiquitous flavonoid widely distributed in plants, on neuropathy, by modulating the expression of NRF-2-dependent antioxidant responsive elements. In this study, the controlled inner and outer surface geometry of the 0.5, 1.0, and 2.0 wt% quercetin-containing electrospun PCL/silk fibrous tubular scaffold fabricated via a modified wound coil collector and L-shaped ground design (WCC-LG) was characterized by FE-SEM, TEM, FFT, FT-IR, and XRD. In addition, two types of neural cell lines, PC12 and S42, were used to evaluate the cell proliferation rate of the different amount of quercetin-loaded PCL/silk tubular scaffolds. Unlabelled Image • We successfully fabricated PCL/silk/quercetin NGCs with topographical cue. • Wound coil collector and L-shaped ground were used for a modified electrospinning. • The proper concentration of quercetin has neuroprotective effects. • The microscale topographical cues can affect the directional growth of neural cells. [ABSTRACT FROM AUTHOR]

The phase stability of near/metastable β-type Ti–Cr-(Mn) alloys with 4.06–13.46 wt% molybdenum equivalent fabricated by rapid solidification process were evaluated using several parameters, i.e. bond order, metal d -orbital energy level and molybdenum equivalent. The microstructural evolution of the near/metastable β-type Ti–Cr and Ti–Cr–Mn alloys was systematically investigated by using optical and transmission electron microscopies. With increasing molybdenum equivalent value in the Ti–Cr-(Mn) alloys, α" martensitic transformation and precipitation of athermal ω phase were strongly suppressed during rapid cooling. Based on microstructural investigation, the β phase stability of the alloys was evaluated using the phase stability index diagram using bond order, metal d -orbital energy level parameters. Moreover, the microstructural evolution depending on the phase stability of Ti–Cr-(Mn) alloys strongly affected to mechanical properties and trade-off behavior between strength and plasticity. Based on these microstructural evolutions and mechanical properties of the Ti–Cr-(Mn) alloys, the phase stability and a relationship between phase stability and mechanical properties of near/metastable β-type titanium alloys were systemically investigated. Image 1 • Phase stability of Ti–Cr-(Mn) alloys was evaluated by theoretical parameters and systematic investigation. • β phase stability strongly affected martensitic transformation and microstructure. • Additional phase boundaries for α" and ω ath phases were added in B o ‾ − M d ‾ phase stability index diagram. • Ti–Cr(Mn) alloys revealed large trade-off behavior on mechanical properties. • Linear relationship between yield strength and [Mo] eq value was identified. [ABSTRACT FROM AUTHOR]

• Y-shaped vascular graft with aligned topography was successfully fabricated. • This electrospinning method is suitable for the fabrication of small-diameter tube. • Aligned fibers altered cell morphology to elongate in a preferred orientation. • This novel vascular graft is mimicked the morphology feature of the native vessel. Tissue-engineered small-diameter artificial blood vessels can provide a promising approach to substantially reduce the functional capacity and risk for vascular morbidity and mortality associated with vascular disease. Despite great achievements in this field over the last decade, the use of a small-diameter fibrous tubular scaffold with a diameter of less than 6 mm has remained elusive. To predict the success of small-diameter vascular transplantation in humans, various animal tests using microscale engineered vessels are needed. For these reasons, we developed a Y-shaped small diameter fibrous tubular graft (500 µm < Φ < 6 mm) with topographical cue using a modified electrospinning technique. Also, the effects of the grafts on human endothelial cell (HUVEC) migration and proliferation were examined under a fluorescence microscope using a z-stack function. The availability of suitable small-diameter and customized structure artificial vessel with nano to microscale topography would increase the fraction of patients surgically treated. [ABSTRACT FROM AUTHOR]

A promising candidate for the development of controlled and targeted nanoscale drug delivery system but less studied so far is calcium carbonate (CaCO 3) in the form of porous polycrystalline vaterite spheres. Vaterite has been shown to exhibit various beneficial properties such as excellent biocompatibility, high drug loading capacity, and pH-sensitive decomposition under mild conditions. However, fabricating vaterite particles with improved porosity, high surface area and loading a payload into the common synthesis method is still a challenge. Here we report on the synthesis of a highly porous, spherical superparamagnetic vaterite particles (PMVP) of size ∼800 nm encapsulating Iron oxide nanoparticles (IONPs) in a one-step reaction and loaded with DOX molecules through electrostatic attractions and physisorption for cancer thermo-chemotherapy application. The main advantage of the PMVP-DOX is that it can be magnetically targeted into the tumor region and once exposed to the tumor tissues characteristic acidic pH, the PMVP nanoparticle dissociates, releasing the DOX and intelligently converts the pH-triggered drug release into a tumor triggered drug release. Simultaneous application of alternating magnetic field (AMF) generates localized heat of the tumor tissues due to the hyperthermic capability of the IONPs in the PMVP and results in the synergistic tumoricidal activities. Image 1 • Design of a highly porous, spherical superparamagnetic submicron vaterite particles. • High drug loading capacity. • Excellent biocompatibility. • PH sensitive decomposition for smart drug delivery. • Alternating magnetic field induced high heating ability. [ABSTRACT FROM AUTHOR]

Numerical simulations become a necessity when experimental approaches cannot cover the required physical and time scale of interest. One of such area is a simulation of long-term host rock behaviors for nuclear waste disposal and simulation tools involved in the assessment must go through rigorous validation tests. The DECOVALEX project (Development of COupled models and their VAlidation against EXperiments) is dedicated to this purpose by international participants. a a www.decovalex.org. This work is part of the ongoing phase DECOVALEX–2023 (D–2023, Task G) particularly aiming to simulate fracture behaviors under various conditions. Here, we cross-verified a variety of numerical methods including continuous and discontinuous approaches against four benchmark exercises with emphasis on numerical accuracy and parameterization of the various numerical approaches. The systematic inter-comparisons of test cases highlight advantages and disadvantages of the different numerical models. Numerical details on discretization effects (e.g. mesh density and orientation) and domain size were investigated in detail for practical applications. It became evident that meticulous attention to mesh resolution and domain size is imperative for achieving accurate numerical simulations, even for static cracks. Moreover, when comparing numerical methods to closed-form solutions for static cracks, all models successfully reproduced the maximum crack opening but encountered challenges near the crack tips. Finally, the paper discusses how to convert between and therefore compare parameters of various numerical approaches. Our benchmark studies reveal that each model necessitates a distinct number of parameters, even in simple scenarios like static crack aperture benchmarks. It is generally more practical to employ fewer parameters to mitigate model over-parameterization and enhance experimental feasibility. • Systematic benchmarks on numerical accuracy & parameterizations for hydro-mechanical fracture mechanics. • Study explores discretization effects and domain size in practical applications. • Compare various numerical approaches' parameterizations. [ABSTRACT FROM AUTHOR]

[Display omitted] • The SPNH/DOX nanoplatform presented controlled drug delivery with a chemo selective approach for chemotherapy. • The copolymer of (NIPAm)-(NHMA) served as temperature-sensitive polymeric carrier. • In-depth study of drug release mechanism using different mathematical equation models. • The synergistic anticancer efficacy of SPNH/DOX was boosted by the combined approach. The study presents a controlled nanoscale drug delivery system mediated by polymeric magnetic nanoparticles. Under an alternating magnetic field (AMF), the magnetic nanoparticles act as internal heating sources that increase the surrounding temperature, provoking polymer transitions and thereby releasing the entrapped drug. We explain the drug-release mechanism using different mathematical models including Higuchi, Korsmeyer–Peppas, Hixson–Crowell, and Kopcha. Our results indicate that doxorubicin (DOX) release follows the Hixson–Crowell model with R2 = 0.99, revealing that the changes in the surface areas of the particles are the main driving force for drug release from poly(N-isopropylacrylamide)/N (hydroxymethyl) acrylamide coated SPIONs (SPNH/DOX) at 43 °C. However, at 37 °C, the drug release occurs by the diffusion mechanism. Moreover, in vitro cell culture assays including CCK-8, FACS, confocal and BIO-TEM images have confirmed cytotoxicity and cellular uptake of SPNH/DOX in CT26 cancer cells. Through a synergetic effect between chemotherapy triggered by AMF application and intracellular hyperthermia, significant tumoricidal effects were achieved in the initial 24 h after treatment. [ABSTRACT FROM AUTHOR]

The effect of interlayer cooling in directed energy deposition on the microstructure and mechanical properties of two titanium alloys (Ti–6Al–4 V and Ti–2.5Fe–4.5Al–0.25Si) was investigated in this study. On the one hand, the general process of directed energy deposition provided sufficient time for element partitioning, resulting in the formation of the isothermal ω. On the other hand, interlayer cooling interfered with element partitioning and isothermal ω formation. It induced the formation of the supersaturated α. The isothermal ω or supersaturated α, generated based on the fabrication conditions, significantly influenced the mechanical properties of these alloys. The higher the β-phase stability of the alloy, the greater is the change in its mechanical properties depending on the fabrication conditions. This study provides guidelines for the design of new alloys manufactured using directed energy deposition. • Two Ti alloys were used to study effect of interlayer cooling on tensile behavior. • Supersaturated α and isothermal ω strongly influences the tensile properties. • Interlayer cooling generated the supersaturated α and increased the strength. • General fabrication generated isothermal ω and decreased the ductility. [ABSTRACT FROM AUTHOR]

The low-cost β-titanium alloys, Ti-Cr-Al-Si, have been designed by the addition of a commercial Al-based die-cast alloy (ADC12, Al 87.38 Cu 0.95 Si 10.65 Mg 0.27 Zn 0.30 Fe 0.32 Mn 0.11 Cr 0.02 in at.%) containing Si content. The microstructural investigation on Ti 84-x Cr 16 (ADC12) x (x = 6, 16 at.%) alloys exhibited that the addition of 6 at.%ADC12 completely dissolved in the β-Ti phase, and exhibited reasonable yield strength by solid solution hardening of the β-Ti phase with large plasticity. The addition of 16 at.%ADC12 effectively reduces the cost of the β-titanium alloys and induces microstructural evolution with formation of Ti-silicide. The β-Ti phase containing high content of solutes and the very fine Ti 5 Si 3 phase that segregated in the interdendritic regions, due to Si solute partitioning during dendritic solidification, mediates outstanding tensile mechanical properties (1015 MPa in yield strength and 17.5% in elongation). These results reveal that the alloy designs using the commercial materials containing various solute elements can facilitate the development of the competitive low-cost β-titanium alloys with excellent mechanical properties. Image 1 • Low-cost β-titanium alloys were designed using cheap commercial ADC12 alloy. • Tensile properties of the alloys improved significantly by addition of ADC12 alloy. • An addition of ADC12 alloy facilitated two strengthening mechanisms. • Solid solution strengthening induced by high Al content dissolved in β-Ti phase. • Precipitation hardening induced by fine Ti-silicide formed during dendritic solidification. [ABSTRACT FROM AUTHOR]

Abstract Here we developed a semi-interpenetrating network (IPN) hydrogel obtained by free radical polymerization to fabricate a coated stent with the aim of incorporating a natural topography present in the human body to improve biological activity. The method involves sandwiching a bare metal stent in the semi-IPN hydrogel via solution cast molding. The bio-functionality of the membrane could be tuned by incorporating Polydopamine into the matrix, and also the mechanical property was optimized by choosing an adequate concentration of acrylamide. The coating containing polydopamine hydrogel showed good mechanical stability under continuous flow condition, as demonstrated by crimping and deployment into a catheter without damage. Stent polymer bonding was enhanced via polydopamine incorporation in the matrix. The non-thrombogenicity of the coating containing hydrogel was confirmed through dynamic hemocompatibility studies in vitro. Vascular simulations, including other biomechanical performance, like durability testing, radial strength, and recoil, were demonstrated. The dopamine containing hydrogel membrane (DCHM) was found to promote cell material interaction due to the ability of the catechol to bind protein and induce HUVECs cytoplasmic spreading, proliferation, and migration, with reduced smooth muscle cell (SMCs) activity. SMCs inhibition correlated well with the amount of incorporated catechol in the matrix. Our results show that this material used as coated stent could be more effective in suppressing platelet aggregation with improved haemocompatibility/biocompatibility for faster re-endothelialization than bare metal stent (BMS). Highlights • 2D modeling of hydrogel coated stent for improved hemodynamics in contrast to bare metal stent was proposed. • Incorporating PU as a second network in the IPN hydrogel greatly improve the mechanical property. • The fabricated membrane creates a stable coating that enable delivery via non-invasive approach (catheter). • Incorporation of Polydopamine in the matrix enhance HUVECs viability/ proliferation and suppresses SMCs viability. [ABSTRACT FROM AUTHOR]

Highlights • The PCL/CA/LA fiber mat was simply obtained by conventional electrospinning method. • The as-fabricated composite membrane was simply treated with CaOH 2. • Calcium lactate (CaL) was synthesized by reaction between LA and CaOH 2. • Cellulose acetate (CA) content was deacetylated into cellulose (CE). • CE and CaL were simultaneously generated in a one-step post-electrospinning process. Abstract Synthetic polymers are easy to process and have excellent mechanical properties but low wettability and poor cell compatibility limit their applications in tissue scaffolding. In this study, a facile procedure was established to regenerate cellulose and calcium lactate (CaL) into a polycaprolactone (PCL) nanofibrous scaffold for tissue engineering applications. Briefly, varying amounts of lactic acid (LA) was mixed with the blend of PCL and cellulose acetate (CA) solutions and electrospun to fabricate an optimal composite PCL/CA/LA fibrous membrane. Later on, as-prepared membranes were treated with calcium hydroxide solution. This process simultaneously converted CA and LA contents into Cellulose and CaL, respectively. In situ regeneration of Cellulose and CaL into the composite fiber remarkably enhanced the biological and physicochemical properties of the composite fiber. This work provides a novel dual-channel strategy for simultaneous regeneration of biopolymer and bioactive molecule into the PCL nanofiber for regenerative medicine and tissue engineering applications. [ABSTRACT FROM AUTHOR]

Abstract Bimodal grain structures are often produced in a metal by employing severe plastic deformation followed by low-homologous-temperature annealing (≤0.4 T m , where T m is melting temperature). Here, a bimodal grain structure was achieved in a Co–20Cr–15W–10Ni–C superalloy via moderate cold rolling (strain ≈0.3) and ultrahigh-homologous-temperature annealing (≥0.8 T m). During annealing, carbide-assisted heterogeneous static-recrystallization played a key role in forming the bimodal grain structure. A 40% increase in combined strength and ductility was observed. Graphical abstract Image 1 Highlights • A bimodal grain structure was achieved in a superalloy without severe deformation. • Cold rolling and ultrahigh-homologous-temperature annealing were carried out. • Carbide-assisted heterogeneous static recrystallization occurred during annealing. • The bimodal grain structure provided 40% higher σ × ε values than uniform grains. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Incorporation proper amount of SIM and β-TCP particles into the FCN mat improved the biomineralization process. • Kopcha model used to study kinetics of the drug release. • The FCN mat improved the osteoblast cell proliferation and adhesion. Abstract The aim of this study is to develop a novel functional composite nanofiber (FCN) loaded beta-tricalcium phosphate (β-TCP) and simvastatin (SIM) FCN mat for bone tissue regeneration. The advantage of electrospinning technique was considered for the uniform distribution of β-TCP and SIM drug. In vitro drug release study performed in phosphate buffer solution (PBS) showed the controlled and sustained release of SIM, and the Kopcha model was used to investigate the drug release mechanism. The morphology of the electrospun nanofibers was investigated using field-emission scanning electron microscopy (FE-SEM). Assessment of the in vitro bioactivity of the nanofibers was carried out in simulated body fluid (SBF). FE-SEM and EDS analysis confirmed the formation of an apatite-like layer. Moreover, in vitr o studies revealed that the FCN mat displayed better cell proliferation and adhesion than merely control fiber. This suggests versatile applications of the fabricated FCN mat for control drug delivery and bone tissue regeneration application. [ABSTRACT FROM AUTHOR]

Highlights • A highly conductive electroactive polyaniline (PANI) was electrodeposited uniformly on titania nanotubes (TNTs) substrate. • Titania nanotubes-polyaniline (TNTs-PANI) showed antibacterial activity and corrosion resistivity. • The biointerface TNTs-PANI was used as basal substrate for PC12 cells regeneration and differentiation. • The flexible TNTs-PANI substrate accelerated the neurites outgrowth of PC12 cells. Abstract Biologically active conjugated polymers, for example polyaniline (PANI), have drawn attention as emerging materials for applications in bio-medical implant devices, due to their inherent abilities with regard to charge-carrier properties, and their ability to immobilize biomolecules or proteins. Herein, we report an electrocoating of PANI on titania nanotubes (TNTs) via electrochemical oxidation of aniline with PANI layers of appropriate thickness (∼274 nm). Uniform titanium oxide nanotubes were first developed from titanium (Ti) foil through an anodization process, followed by calcination to obtain high purity TNTs vertically aligned on a Ti substrate. These had a large surface area, controllable tube height and diameter, and were highly biocompatible, and doping with PANI further improved their properties, like being antibacterial, having a lower charge transfer resistance (22.51 Ω) and strong anti-corrosion behavior (E corr ∼ − 184 mV, I corr ∼ 9.7 × 10−7 Amp). In vitro experiments revealed that the cellular functions of PC12 and S42 cells on TNTs-PANI scaffolds show characteristic improvement in proliferation and differentiation owning to approach neuronal cells activation associated with axonal growth and migration in the peripheral nervous system (PNS). Thus, the flexible bioactive substrate is capable of stimulating neuronal cells, and can inspire neural transduction through direct neural interfaces. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • RH affects the generation of the 3D cotton-like piezoelectric electrospun scaffold. • When RH was increased to critical point, repulsion of spinning-jet was raised. • Raised repulsion helped the fibers to electrospin in the form of fluffy construct. Abstract Three-dimensional (3D), highly porous, and low-density fibrous scaffolds have attracted significant interest in recent years for applications in tissue engineering. However, the fabrication of 3D fluffy fibrous piezoelectric scaffolds remains a challenge. In this study, we report the dramatic effect that relative humidity (RH) has on the deposition of 3D cotton-like constructs composed of polyvinylidene fluoride (PVDF) piezoelectric nanofibers mixed with Barium Titanate (BT) and multiwalled-carbon nanotubes (MWCNTs). The 30 mm diameter deposits were fabricated under variable humidity conditions while all other parameters were kept constant. Two types of fibrous architecture, 3D fluffy and two-dimensional (2D) membrane types, are recognized, as the RH during electrospinning varies. A fiber morphology transition takes place at certain RH, and the 3D cotton-like nanofibrous structure has been optimized above 90% RH. The fabrication of the 3D cotton-like fibrous piezoelectric scaffold may provide new insights for various applications in tissue engineering. [ABSTRACT FROM AUTHOR]

Abstract In recent years, capacitive deionization (CDI) has attracted intensive research due to its environmentally-friendly nature and low power requirement. Although the characteristics of titania (TiO 2) and zirconia (ZrO 2) are almost the same, ZrO 2 has not attracted the same attention since the characteristics of the carbonaceous material need to be modified to enhance its performance as an electrode in CDI cells. In this study, the wettability and electrochemical behavior of activated carbon (AC), as a widely used, effective, and inexpensive material, was distinctively improved by doping with zirconia nanoparticles. The introduced AC/ZrO 2 nanocomposite was fabricated using the alkaline hydrothermal method. Investigation of the surface morphology, phase and crystallinity by SEM, TEM, XPS, and XRD demonstrated the successful doping of AC by zirconia nanoparticles. Interestingly, the wettability measurement showed excellent enhancement, since the water contact angles of pristine and doped AC are 45° and 148°, respectively. The electrochemical experiments demonstrated that the synthesized composite (AC/ZrO 2) has a specific capacitance of 282.8 F g−1, which is higher than that for AC (207.5 F g−1). Due to the significant improvement in wettability and specific capacitance, the desalination performance and the salt ion electrosorption capacity were also enhanced: 40.4% and 68.5%, and 2.82 and 4.79 mg/g for AC and AC/ZrO 2 , respectively. Moreover, the introduced AC/ZrO 2 revealed 99% remaining desalination retention suggesting high stability. Overall, this study demonstrates ZrO 2 is an effective, stable, and environmentally safe material for improving the performance of carbonaceous CDI electrodes. Graphical abstract Image 1 Highlights • ZrO 2 NPs/AC is introduced as effective CDI electrode material. • The salt removal efficiency has been improved to 68.5%. • Good performance is due to improving the specific capacitance. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract In the present work, polypyrrole hollow fibers (PPy-HFs) were fabricated by sacrificial removal of soft templates of electrospun polycaprolactone (PCL) fibers with polypyrrole (PPy) coating through chemical polymerization of pyrrole monomer. Different physicochemical properties of as-fabricated PPy-HFs were then studied by Field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), Fourier transform infra-red (FT-IR) spectroscopy, Differential scanning calorimetry/Thermogravimetric analysis (DSC/TGA), and X-ray photoelectron spectroscopy (XPS). The photothermal activity of PPy-HF was studied by irradiating 808-nm near infra-red (NIR) light under different power values with various concentrations of PPy-HFs dispersed in phosphate buffer solution (PBS, pH 7.4). These PPy-HFs exhibited enhanced photothermal performance compared with polypyrrole nanoparticles (PPy-NPs). Furthermore, these PPy-HFs showed photothermal effect that was laser-power- and concentration-dependent. The photothermal toxicity of the resulting nanofiber was evaluated using cell counting kit-8 (CCK-8) and live and dead cell assays. Results showed that these PPy-HFs were more effective in killing cancer cells under NIR irradiation. In contrast, hollow-fiber showed no cytotoxicity without NIR exposure. Among different nanofiber formulations, PPy-160 exhibited the highest photothermal toxicity. It could be explained by its enhanced photothermal performance compared to other specimens. The resulting PPy-HFs showed superior drug-loading capacity to PPy-NPs. This might be attributed to adequate binding of the drug into both luminal and abluminal hollow-fiber surfaces. Fabrication of this substrate type opens a promising new avenue for architectural design of biocompatible organic polymer for biomedical field. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Ti-23Nb-1Ta-2Hf-O shows gum-metal-like superproperties. • Nanodomain, giant fault, and ω phase transformation were observed. • Three magic numbers were not sufficient to obtain superproperties. • Equivalent β-stabilizer content should be considered to design gum metal. Abstract The conditions needed to design gum metal were reconsidered based on the equivalent β stabilizer content required to obtain compositional/microstructural variability in a Ti-24(Nb + Ta + V)-(Zr, Hf)-O system. It was found that 90% cold-worked Ti-23Nb-1Ta-2Hf-O alloy exhibits gum-metal-like superproperties such as ultrahigh strength, ultralow elastic modulus, superelasticity, superplasticity, and Elinvar behavior. These multi-functions can be achieved even with the deformation-induced ω phase if nanodomains and giant faults exist. This suggests that not only the three electronic magic numbers, but also the equivalent β stabilizer content should be considered to attain the superproperties. [ABSTRACT FROM AUTHOR]

In this work, titanium oxide nanotubes (TNTs) have been developed via electrochemical anodization process, followed by potentiostatic electropolymerization of aniline monomer to achieve TNTs coated polyaniline (PANI) substrate using cyclic voltammetry method at low temperature. Prior to PANI decoration, crystallinity of titanium oxide nanotubes (TNTs) was obtained by annealing the substrate at 420 °C for two hours. The physicochemical characterization of the as-prepared TNTs and TNTs/PANI were analyzed using FE-SEM, AFM, XRD and FT-IR techniques. A coating of PANI forms a sheath around the nanotubes and protects them from metallic corrosion. Large surface area to volume ratio of TNTs showed improved properties in biocompatibility, thermal stability, electrical conductivity, biomineralization and hydrophilicity after coating with PANI, an electroactive conducting polymer. In addition, the TNTs/PANI exhibited an effective platform to enhance attachment, development and proliferation of preosteoblast (MC3T3-E1) cells which opens a new avenue in the realm of bone tissue engineering. The cells’ morphology to their surrounding topography, development, or proliferation, and osteogenic-related markers (such as ALP increased level, collagen type I secretion) were also analysed. Such types of surface modification tailoring on titanium nanotubes could offer a potential and a promising scaffold material for biomedical implantation in bone tissue engineering. [ABSTRACT FROM AUTHOR]

Coated stents are classified as new generation stents wrapped with a thin polymeric membrane for the treatment of numerous vascular irregularities ranging from aneurysms to vascular leaks. Compared to partially covered and bare metal stents (BMS), fully covered stents promote less tissue granulation and suppress thrombosis, and can be designed to be post-operative retrievable. Fabrication method and material selection play significant roles in coated stent application, due to commercially available coated stents induce some degree restenosis. We have successfully fabricated a non-thrombotic and biocompatible fully coated stent made of a semi-interpenetrating network (IPN) hydrogel composed of acrylic acid (AA), dopamine methacrylamide (DMA), and methyl methacrylate (MMA) terpolymer (P(AA-co-MMA-co-DMA)/PU, incorporated with polyurethane (PU). We utilize a conventional mold casting method to fabricate a uniform covered stent, with the stent struts fully embedded within the hydrogel membrane. Firm polymer-stent bonding was achieved by introducing DMA into the matrix. We characterized the membrane by conducting platelet adhesion/activation studies followed by hemolysis and inflammatory potential evaluation which supports a non-thrombogenicity of the P(AA-co-MMA-co-DMA)/PU semi-IPN hydrogel membrane. The quality of the coated hydrogel membrane was evaluated by scanning electron microscopy (SEM); mechanical stability of the layer was analyzed by peeling test; tensile test, and multiple physical deformations tests. Further evaluation will be carried out in the near future to evaluate the potential in vivo application of this new semi-IPN hydrogel coated stent to remedy non-vascular leaks and other strictures. [ABSTRACT FROM AUTHOR]

Low-density, high porous bioactive fibrous scaffolds have attracted significant attention for tissue engineering. However, fabrication of biomimetic fibrous scaffolds having three-dimensional architecture along with bioactive materials still remains a challenging task for biomaterial scientists. Herein, for the first time, we developed a novel strategy to fabricate highly porous ß-tricalcium phosphate (ß-TCP) incorporated Poly ( l -lactide) (PLLA) fibrous scaffold for bone tissue engineering. Blending of PLLA with its monomer, lactic acid (LA) produced the fluffy type highly porous nanofibrous mesh. The mass composition of the constituents of the blend solution was varied to control the morphology and packing of the nanofibers in the scaffold. The results showed that LA played the vital role in the generation of the 3D fluffy type fibrous mesh. ß-TCP particles were incorporated in the blend solution prior to the electrospinning solution, to fabricate ß-TCP incorporated PLLA fibrous scaffold. Later, LA was leached out by washing with distilled water, to avoid its adverse effect on biocompatibility. Digital and SEM images revealed the formation of spongy, low-density fibrous mesh. TEM images, IR, and TGA analysis confirmed the presence of ß-TCP nanoparticles in the nanofibers after leaching of LA. Incorporation of the ß-TCP enhanced the water uptake ability, in vitro bio-mineralization, and bioactivity of the fibrous scaffold. Confocal microscopy images showed that the pre-osteoblast cells seeded on the fluffy type fibrous mesh infiltrated throughout the depth of the scaffold, compared to no penetrating growth for the 2D scaffold. In vitro biocompatibility evaluated by CCK assay showed significantly higher growth for cells on the fluffy type scaffold, compared to the 2D scaffold. We demonstrated scaffolds suitability for biocompatibility and osteogenic differentiation of hMSCs as well. We believe that the fabrication of bioactive particle incorporated highly porous 3D fibrous scaffold will open a new avenue for tissue engineering applications. [ABSTRACT FROM AUTHOR]

Herein, we engineered a self-electrical stimulated double-layered nerve guidance conduit (NGC) assembled from electrospun mats with an aligned oriented inward layer covered with a random oriented outer layer. The biomimetic NGC can be achieved from chitosan grafted polyurethane with well-dispersed functionalized multiwall carbon nanotubes ( f MWCNTs) nanofibrous mats after a uniform coating of polypyrrole (PPy). The structural framework of interconnected NGC exhibited cellular biomaterial interface and improved the physicochemical properties, including electrical conductivity, mechanical strength, and cytocompatibility, serving as natural hosting substrate to natural extracellular matrices (ECM) for vital roles in nerve tissue engineering. The regrowth, proliferation, and migration, of Schwann cells (S42) and the differentiation of rat pheochromocytoma cells (PC12) were greatly accelerated on the aligned oriented mats as compared to the randomly oriented mats during in vitro cell cultures. The morphology of the spontaneous outgrowth and phenotype of neurite bundles were preferentially guided along the axis of the aligned oriented nanofibers, which maintains a strong adaptability in axonal regeneration. In addition, the differentiation of PC12 cells cultured on as-fabricated NGCs were evaluated from cDNA gene expression. It is hoped that the results will contribute to the efficient application of designed NGCs and can be used in therapeutic strategies for treating injured sites and stimulate recovery from substantial damage to nerve cells. [ABSTRACT FROM AUTHOR]

Chemothermal brachytherapy seeds have been developed using a combination of polymeric dual drug chemotherapy and alternating magnetic field induced hyperthermia. The synergistic effect of chemotherapy and hyperthermia brachytherapy has been investigated in a way that has never been performed before, with an in-depth analysis of the cancer cell inhibition property of the new system. A comprehensive in vivo study on athymic mice model with SCC7 tumor has been conducted to determine optimal arrays and specifications of the chemothermal seeds. Dual drug chemotherapy has been achieved via surface deposition of polydopamine that carries bortezomib, and also via loading an acidic pH soluble hydrogel that contains 5-Fluorouracil inside the chemothermal seed; this increases the drug loading capacity of the chemothermal seed, and creates dual drug synergism. An external alternating magnetic field has been utilized to induce hyperthermia conditions, using the inherent ferromagnetic property of the nitinol alloy used as the seed casing. The materials used in this study were fully characterized using FESEM, H 1 NMR, FT-IR, and XPS to validate their properties. This new approach to experimental cancer treatment is a pilot study that exhibits the potential of thermal brachytherapy and chemotherapy as a combined treatment modality. [ABSTRACT FROM AUTHOR]

Titanium implants are extensively used in biomedical applications due to their excellent biocompatibility, corrosion resistance, and superb mechanical stability. In this work, we present the use of polycaffeic acid (PCA) to immobilize metallic silver on the surface of titanium materials to prevent implant bacterial infection. Caffeic acid is a plant-derived phenolic compound, rich in catechol moieties and it can form functional coatings using alkaline buffers and with UV irradiation. This combination can trigger oxidative polymerization and deposition on the surface of metallic substrates. Using PCA can also give advantages in bone implants in decreasing inflammation by decelerating macrophage and osteoclast activity. Here, chemical and physical properties were investigated using FE-SEM, EDS, XPS, AFM, and contact angle. The in vitro biocompatibility and antibacterial studies show that PCA with metallic silver can inhibit bacterial growth, and proliferation of MC-3T3 cells was observed. Therefore, our results suggest that the introduced approach can be considered as a potential method for functional implant coating application in the orthopedic field. [ABSTRACT FROM AUTHOR]

Designing a piezoelectric energy harvester (PEH) with high power density and high fatigue resistance is essential for the successful replacement of the currently using batteries in structural health monitoring (SHM) systems. Among the various designs, the PEH comprising of a cantilever structure as a passive layer and piezoelectric single crystal-based fiber composites (SFC) as an active layer showed excellent performance due to its high electromechanical properties and dynamic flexibilities that are suitable for low frequency vibrations. In the present study, an effort was made to investigate the reliable performance of hard and soft SFC based PEHs. The base acceleration of both PEHs is held at 7 m/s2 and the frequency of excitation is tuned to their resonant frequency (fr) and then the output power (Prms) is monitored for 107 fatigue cycles. The effect of fatigue cycles on the output voltage, vibration displacement, dielectric, and ferroelectric properties of PEHs was analyzed. It was noticed that fatigue-induced performance degradation is more prominent in soft SFC-based PEH (SS-PEH) than in hard SFC-based PEH (HS-PEH). The HS-PEH showed a slight degradation in the output power due to a shift in fr, however, no degradation in the maximum power was noticed, in fact, dielectric and ferroelectric properties were improved even after 107 vibration cycles. In this context, the present study provides a pathway to consider the fatigue life of piezoelectric material for the designing of PEH to be used at resonant conditions for long-term operation. [ABSTRACT FROM AUTHOR]

Stainless steel as a biomedical implant material has been studied in various fields and in various forms, such as vascular stents, bone plates, dental screws, and artificial hip and bone material. In this study, we used polycaffeic acid (PCA), a natural phenolic compound, to coat the surface of medical grade stainless steel to provide added potential medicinal effects by virtue of its inherent anti-inflammatory, antiviral, antifibrosis, antithrombosis, and antihypertensive characteristics. We did this via UV irradiation under an alkaline state to solve the cost and time problems of other existing coating methods. The physicochemical properties of the samples were investigated through field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), contact angle, FTIR, and X-ray photoelectron spectroscopy (XPS). Surface bioactivity using NIH-3T3 cell lines were observed in vitro. We expect that the proposed methodology may contribute to the field of study of implantable metallic devices. [ABSTRACT FROM AUTHOR]

Bone tissue engineering is an interdisciplinary field where the principles of engineering are applied on bone-related biochemical reactions. Scaffolds, cells, growth factors, and their interrelation in microenvironment are the major concerns in bone tissue engineering. Among many alternatives, electrospinning is a promising and versatile technique that is used to fabricate polymer fibrous scaffolds for bone tissue engineering applications. Copolymerization and polymer blending is a promising strategic way in purpose of getting synergistic and additive effect achieved from either polymer. In this review, we summarize the basic chemistry of bone, principle of electrospinning, and polymers that are used in bone tissue engineering. Particular attention will be given on biomechanical properties and biological activities of these electrospun fibers. This review will cover the fundamental basis of cell adhesion, differentiation, and proliferation of the electrospun fibers in bone tissue scaffolds. In the last section, we offer the current development and future perspectives on the use of electrospun mats in bone tissue engineering. [ABSTRACT FROM AUTHOR]

Mesoporous architectures are remarkable electrode materials for energy storage system due to their large number of active sites and high surface area. Here we report, mesoporous MoS 2 particles (pore diameter 34.04 nm) well attached to the surface of thin layered reduced graphene oxide (rGO) via an ultrasonic chemical method for supercapacitor applications. The rGO not only increases the conductivity of MoS 2 but also provides a substrate for the attachment of MoS 2 with low aggregation. The porous MoS 2 provides a large surface area and sufficient way for the fast transport of electrolyte ions toward electrode materials. As a result, the synthesized MoS 2 /rGO composites exhibited excellent electrochemical performance with a specific capacitance 314.5 F/g in 2M KOH aqueous solution at a scan rate of 10 mV/s and excellent specific capacitance retention (80.02%) after 1000 cycles in a three electrode system for energy storage applications. [ABSTRACT FROM AUTHOR]

Herein, we present a novel strategy to fabricate high porous fluffy type Poly ( L -lactide) (PLA) nanofibrous scaffold for tissue regeneration. Low-density nanofibrous scaffold was fabricated by electrospinning the blend of PLA and lactic acid (LA), followed by selective leaching of LA. Digital images, Field Emission Scanning Electron Microscope (FE-SEM) images, Infra-red (IR) spectra, Thermogravimetric analysis (TGA) curves revealed the formation of the low density biomimetic nanofibrous mesh. In vitro cell compatibility results indicated that as-fabricated PLA nanofibrous scaffold enhanced the cell proliferation and growth compared to the corresponding two-dimensional nanofibrous scaffold. Furthermore, confocal microscopy images showed that cells seeded on the fluffy type nanofibrous mesh infiltrated throughout the depth of the scaffold, compared to no penetrating growth for the two-dimensional scaffold. The fabrication of such fascinating materials may provide new insights into the design and development of the low density nanofibrous scaffolds for various tissue engineering applications. [ABSTRACT FROM AUTHOR]

Cellulose I and II polymorphs were isolated from Capsosiphon fulvescens (CF) using the conventional method of extraction and direct mercerization of raw sample, respectively. The morphological and structural differences between the isolated polymorphs were studied by FTIR, FESEM and XRD. Direct mercerization of raw CF yielded the transformation of highly crystalline cellulose I (81.3%) to II (63.7%) as observed in the shifting of XRD patterns. The derived cellulose I and II were hydrolyzed (60% w/w H 2 SO 4 , 55 °C, 1 h, 10 mL/g) to obtain the spindle-shaped cellulose nanocrystals. Cellulose nanocrystal I was observed to have a mean thickness and length of 12.67 ± 2.69 and 92.31 ± 21.31 nm, respectively; while cellulose nanocrystal II has a mean thickness and length of 15.58 ± 2.85 and 78.09 ± 18.22 nm, respectively. Furthermore, a fiber-like mat assembly, which could be used as supplement support structure for tissue engineering, was obtained after subjecting the aqueous cellulose nanocrystal suspensions to freeze-drying. A possible application of this material can be as a biocompatible and biodegradable composite for tissue engineering and other biomedical applications. [ABSTRACT FROM AUTHOR]

We prepared Janus microspheres based on sodium alginate for the encapsulation of mesenchymal stem cells (MSC) in one compartment and iron oxide nanoparticles (IONP) or a drug in the second compartment. 4% percent sodium alginate solution was allowed to pass through a septum-theta capillary device and react with 2.5% calcium chloride to allow crosslinking to occur in the solution, forming calcium alginate Janus microspheres. Physico-chemical characterization of microspheres was done by FTIR, TGA, and XRD after loading of stem cells and IONP/drug. The mechanical integrity of microspheres was tested at different time points, which showed that 4% alginate microspheres were mechanically stable for a long period of time. Live/dead staining of MSCs alone and the MTS assay of MSCs and DMSO co-loaded were performed, which showed less toxicity to MSC in the Janus configuration. IONP/MSC-loaded Janus microspheres were tested by magnetic manipulation for targeted MSC delivery for cartilage repair using an electromagnetic manipulation (EMM) device. Janus microspheres can be used for targeted stem cell/drug delivery using EMM for cartilage repair in the near future. [ABSTRACT FROM AUTHOR]

Through exhaustive extraction via successive alkali and bleaching treatments cellulose was isolated from lettuce. The isolated cellulose was hydrolyzed using 64 wt% H 2 SO 4 at 55 °C under constant stirring for 1 h to obtain cellulose nanocrystals (CNCs). Characterizations such as SEM, TEM, FTIR, TGA and XRD were done in order to determine differences in the physico-chemical characteristics of cellulose after each treatment step. The isolated CNCs have mean dimensions of 237 ± 26, 33 ± 12 and 32 ± 7 nm in length, thickness and height, respectively. These nanocrystals were incorporated to the formulations that were used to fabricate different chitosan-g- d , l -lactic acid (CgLA) scaffolds. Amide linkage formation between chitosan and lactic acid and further removal of water was facilitated by oven-drying under vacuum at 80 °C. Results show that an increase in the concentration of CNCs added, increase in porosity, degradability, drug release property and cell viability were observed from the fabricated composite scaffolds. These results can provide information on how nanofillers such as CNCs can alter the properties of tissue scaffolds through the chemical properties and interactions they provide. Moreover, these characteristics can give new properties that are necessary for certain tissue engineering applications. [ABSTRACT FROM AUTHOR]

In this study, a novel composite of Cu–Al layered double hydroxide (LDH) nanosheets and g-C3N4-covered Ni-foam was fabricated via a simple and facile two-step process. First, g-C3N4 sheets were deposited on Ni-foam by via electrodeposition method on a three-electrode system (Ni-foam@g-C3N4) and then, Cu–Al LDH nanosheets were grown on the Ni-foam via in situ redox reaction using a hydrothermal process (Ni-foam@Cu–Al LDH/g-C3N4). The FE-SEM image confirmed that the Cu–Al LDH nanosheets arose vertically and were anchored on the surface of electrodeposited g-C3N4 sheets, thus generating unique 3D porous interconnected networks. The electrochemical capacitive performances of the as-prepared samples were evaluated by cyclic volatammetry (CV), galvanostatic charge/discharge tests, and electrochemical impedance spectra (EIS) Nyquist plots. The specific capacitances of the Ni-foam@Cu–Al LDH/g-C3N4 nanocomposite measured from the CV curve (770.98 F g−1 at 50 mV s−1) and the galvanostatic charge/discharge curve (831.871 at 0.4 A g−1) were significantly higher than the others. Moreover, the Ni-foam@Cu–Al LDH/g-C3N4 nanocomposite revealed a remarkable high-current capacitive behavior and the capacitance retention could be maintained at 92.71% even after 5000 cycles of CV. Thus, the obtained results demonstrated that the as-prepared nanocomposite has great potential to be used as a novel supercapacitor electrode. [ABSTRACT FROM AUTHOR]

Depositing of hierarchical ZnO nanostructures on electrospun nanofibers and their proper attachment has gained significant interest for myriad applications. However, the weak attachment of such nanostructures to the nanofiber surface limits their practical applications. In this study, a simple and efficient method has been developed for preparing hierarchical ZnO nanorod deposited polyurethane (PU) nanofiber by combining electrospinning, surface functionalization and hydrothermal treatment. Electrospun PU nanofibers were coated with polydopamine (Pdopa) via dip coating method. The resulting Pdopa coated PU nanofibrous mat was soaked in aqueous ZnO nanoparticles (ZnONPs) solution in order to seed the metal-oxide particles on its surface. Later, ZnO nanorods (ZNRs) were grown on the ZnO-seeded electrospun PU nanofiber via a hydrothermal process. X-ray photoelectron spectroscopy (XPS), Field-Emission Scanning electron microscopy (FE-SEM), X-ray diffraction pattern (XRD) and infra-red (IR) spectra indicated that ZnO nanorods firmly adhered to the functionalized PU nanofiber surface and had high photocatalytic/antimicrobial activity at the low-intensity UV-LED device with good reusability. The catechol group of Pdopa not only causes adhesion of ZnO nanostructures, but also act as an electron trap, preventing the recombination of e-h pairs and thereby improving the photocatalytic efficiency. We believe that the fabricated composite membrane with antifouling effect and photocatalytic activity is a potential candidate for organic pollutant degdration and wastewater purification. [ABSTRACT FROM AUTHOR]